Detailed Predictions for: Marshall
Launch Altitude (f): 4040
LZ Altitude (f): 1700
Sounding

Station:

KNKX

Date/Time:

22 APR 2018

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)
High
Temp

Puddle
Temp

Wind
(mph)
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
5 AM Sun 58 56 N 10 2680 4040 0 Blue 0
6 AM Sun 60 58 N 9 2680 4040 0 Blue 0
7 AM Sun 63 61 N 8 2680 4040 0 Blue 0
8 AM Sun 65 64 N 7 2680 4040 0 Blue 0
9 AM Sun 68 68 NW 6 2680 4040 0 Blue 0
10 AM Sun 69 71 W 6 4416 4040 0 Blue 0
11 AM Sun 72 75 SW 6 6718 5264 1224 Blue 3
12 Noon Sun 75 79 SW 7 11658 7433 3393 Blue 7
1 PM Sun 78 83 SW 8 12093 11735 7695 Blue 11
2 PM Sun 80 84 SW 10 12248 11821 7781 Blue 12
3 PM Sun 80 83 SW 12 12093 11735 7695 Blue 11
4 PM Sun 80 81 SW 12 11847 9953 5913 Blue 9
5 PM Sun 77 76 SW 13 7548 5730 1690 Blue 4
6 PM Sun 73 71 SW 10 4416 4040 0 Blue 0
7 PM Sun 68 66 SW 8 2680 4040 0 Blue 0
8 PM Sun 64 62 S 3 2680 4040 0 Blue 0
9 PM Sun 61 59 SE 3 2680 4040 0 Blue 0
10 PM Sun 60 58 SE 5 2680 4040 0 Blue 0
11 PM Sun 59 57 E 5 2680 4040 0 Blue 0
12 Midnight Mon 58 56 E 5 2680 4040 0 Blue 0
1 AM Mon 58 56 E 5 2680 4040 0 Blue 0
2 AM Mon 57 55 E 2 2680 4040 0 Blue 0
3 AM Mon 56 54 E 2 2680 4040 0 Blue 0
4 AM Mon 55 53 NE 2 2680 4040 0 Blue 0
5 AM Mon 55 53 NE 2 2680 4040 0 Blue 0
6 AM Mon 57 55 NE 2 2680 4040 0 Blue 0
7 AM Mon 60 58 NE 2 2680 4040 0 Blue 0
8 AM Mon 64 63 S 1 2680 4040 0 Blue 0
9 AM Mon 66 66 S 2 2680 4040 0 Blue 0
10 AM Mon 68 70 S 2 3448 4040 0 Blue 0
11 AM Mon 70 74 S 6 6173 4375 335 Blue 2
12 Noon Mon 73 78 S 6 10220 6616 2576 Blue 6
1 PM Mon 76 81 S 7 11847 9953 5913 Blue 9
2 PM Mon 78 83 SW 9 12093 11735 7695 Blue 11
3 PM Mon 78 81 SW 10 11847 9953 5913 Blue 9
4 PM Mon 79 80 SW 10 11760 8694 4654 Blue 8
5 PM Mon 77 76 SW 10 7548 5730 1690 Blue 4
6 PM Mon 73 71 SW 8 4416 4040 0 Blue 0
7 PM Mon 70 68 S 5 2680 4040 0 Blue 0
8 PM Mon 66 64 S 2 2680 4040 0 Blue 0
9 PM Mon 63 61 S 1 2680 4040 0 Blue 0
10 PM Mon 61 59 SE 1 2680 4040 0 Blue 0
11 PM Mon 60 58 E 2 2680 4040 0 Blue 0
12 Midnight Tue 59 57 E 2 2680 4040 0 Blue 0
1 AM Tue 58 56 E 2 2680 4040 0 Blue 0
2 AM Tue 57 55 E 2 2680 4040 0 Blue 0
3 AM Tue 56 54 E 2 2680 4040 0 Blue 0
4 AM Tue 55 53 NE 3 2680 4040 0 Blue 0
5 AM Tue 55 53 NE 2 2680 4040 0 Blue 0
6 AM Tue 57 55 NE 5 2680 4040 0 Blue 0
7 AM Tue 60 58 NE 3 2680 4040 0 Blue 0
8 AM Tue 63 62 NW 0 2680 4040 0 Blue 0
9 AM Tue 66 66 S 1 2680 4040 0 Blue 0
10 AM Tue 69 71 S 2 4416 4040 0 Blue 0
11 AM Tue 71 73 S 7 5770 4040 0 Blue 1
12 Noon Tue 74 77 SW 7 8960 6141 2101 Blue 5
1 PM Tue 77 80 SW 7 11760 8694 4654 Blue 8
2 PM Tue 80 83 SW 9 12093 11735 7695 Blue 11
3 PM Tue 80 82 SW 10 11938 11599 7559 Blue 10
4 PM Tue 81 81 SW 12 11847 9953 5913 Blue 9
5 PM Tue 78 77 SW 12 8960 6141 2101 Blue 5
6 PM Tue 74 72 SW 9 5312 4040 0 Blue 0
7 PM Tue 68 66 S 7 2680 4040 0 Blue 0
8 PM Tue 63 61 S 2 2680 4040 0 Blue 0
9 PM Tue 60 58 S 2 2680 4040 0 Blue 0
10 PM Tue 58 56 S 2 2680 4040 0 Blue 0
11 PM Tue 57 55 SE 3 2680 4040 0 Blue 0
12 Midnight Wed 56 54 SE 3 2680 4040 0 Blue 0
1 AM Wed 56 54 SE 3 2680 4040 0 Blue 0
2 AM Wed 55 53 E 2 2680 4040 0 Blue 0
3 AM Wed 54 52 E 2 2680 4040 0 Blue 0
4 AM Wed 52 50 E 2 2680 4040 0 Blue 0
5 AM Wed 52 50 E 1 2680 4040 0 Blue 0
6 AM Wed 54 52 E 1 2680 4040 0 Blue 0
7 AM Wed 56 54 E 1 2680 4040 0 Blue 0
8 AM Wed 60 59 S 5 2680 4040 0 Blue 0
9 AM Wed 62 62 S 5 2680 4040 0 Blue 0
10 AM Wed 65 66 S 5 2680 4040 0 Blue 0
11 AM Wed 67 70 SW 7 3448 4040 0 Blue 0
12 Noon Wed 70 74 SW 7 6173 4375 335 Blue 2
1 PM Wed 72 76 SW 7 7548 5730 1690 Blue 4
2 PM Wed 75 79 SW 10 11658 7433 3393 Blue 7
3 PM Wed 76 78 SW 10 10220 6616 2576 Blue 6
4 PM Wed 76 77 SW 10 8960 6141 2101 Blue 5
5 PM Wed 74 73 SW 12 5770 4040 0 Blue 1
6 PM Wed 71 69 SW 12 2680 4040 0 Blue 0
7 PM Wed 67 65 SW 12 2680 4040 0 Blue 0
8 PM Wed 63 61 S 7 2680 4040 0 Blue 0
9 PM Wed 61 59 S 7 2680 4040 0 Blue 0
10 PM Wed 59 57 S 7 2680 4040 0 Blue 0
11 PM Wed 58 56 SE 1 2680 4040 0 Blue 0
12 Midnight Thu 57 55 SE 1 2680 4040 0 Blue 0
1 AM Thu 56 54 SE 1 2680 4040 0 Blue 0
2 AM Thu 55 53 SE 0 2680 4040 0 Blue 0
3 AM Thu 54 52 SE 0 2680 4040 0 Blue 0
4 AM Thu 53 51 SE 0 2680 4040 0 Blue 0
5 AM Thu 53 51 E 1 2680 4040 0 Blue 0
6 AM Thu 55 53 E 1 2680 4040 0 Blue 0
7 AM Thu 57 55 E 1 2680 4040 0 Blue 0
8 AM Thu 60 59 SE 5 2680 4040 0 Blue 0
9 AM Thu 63 63 SE 5 2680 4040 0 Blue 0
10 AM Thu 66 68 SE 5 2680 4040 0 Blue 0
11 AM Thu 68 71 S 7 4416 4040 0 Blue 0
12 Noon Thu 71 75 S 7 6718 5264 1224 Blue 3
1 PM Thu 74 78 S 7 10220 6616 2576 Blue 6
2 PM Thu 75 79 SW 10 11658 7433 3393 Blue 7
3 PM Thu 76 78 SW 10 10220 6616 2576 Blue 6
4 PM Thu 76 77 SW 10 8960 6141 2101 Blue 5
5 PM Thu 74 73 SW 10 5770 4040 0 Blue 1
6 PM Thu 71 69 SW 10 2680 4040 0 Blue 0
7 PM Thu 68 66 SW 10 2680 4040 0 Blue 0
8 PM Thu 64 62 S 7 2680 4040 0 Blue 0
9 PM Thu 62 60 S 7 2680 4040 0 Blue 0
10 PM Thu 60 58 S 7 2680 4040 0 Blue 0
11 PM Thu 58 56 SE 2 2680 4040 0 Blue 0
12 Midnight Fri 57 55 SE 2 2680 4040 0 Blue 0
1 AM Fri 56 54 SE 2 2680 4040 0 Blue 0
2 AM Fri 55 53 SE 2 2680 4040 0 Blue 0
3 AM Fri 53 51 SE 2 2680 4040 0 Blue 0
4 AM Fri 52 50 SE 2 2680 4040 0 Blue 0
5 AM Fri 52 50 SE 2 2680 4040 0 Blue 0
6 AM Fri 53 51 SE 2 2680 4040 0 Blue 0
7 AM Fri 55 53 SE 2 2680 4040 0 Blue 0
8 AM Fri 58 57 S 5 2680 4040 0 Blue 0
9 AM Fri 61 61 S 5 2680 4040 0 Blue 0
10 AM Fri 64 66 S 5 2680 4040 0 Blue 0
11 AM Fri 66 70 S 7 3448 4040 0 Blue 0
12 Noon Fri 70 75 S 7 6718 5264 1224 Blue 3
1 PM Fri 72 77 S 7 8960 6141 2101 Blue 5
2 PM Fri 74 78 S 10 10220 6616 2576 Blue 6
3 PM Fri 75 78 S 10 10220 6616 2576 Blue 6
4 PM Fri 74 75 S 10 6718 5264 1224 Blue 3
5 PM Fri 73 72 SW 13 5312 4040 0 Blue 0
6 PM Fri 70 68 SW 13 2680 4040 0 Blue 0
7 PM Fri 67 65 SW 13 2680 4040 0 Blue 0
8 PM Fri 64 62 S 8 2680 4040 0 Blue 0
9 PM Fri 61 59 S 8 2680 4040 0 Blue 0
10 PM Fri 59 57 S 8 2680 4040 0 Blue 0
11 PM Fri 57 55 S 2 2680 4040 0 Blue 0
12 Midnight Sat 56 54 S 2 2680 4040 0 Blue 0
1 AM Sat 55 53 S 2 2680 4040 0 Blue 0
2 AM Sat 54 52 SE 1 2680 4040 0 Blue 0
3 AM Sat 53 51 SE 1 2680 4040 0 Blue 0
4 AM Sat 52 50 SE 1 2680 4040 0 Blue 0

DISCLAIMER: These estimates are intended to assist in daily site selection only.  No warranty is made concerning the accuracy of these estimates.  These estimates cannot be used to determine if conditions are safe for flying.  Conditions should be evaluated at the launch site by experienced pilots before launching.

Sounding: This is the site at which the weather balloon was released.  If the flying site predicted is far from the sounding site, the estimate is not valid.  Also, the sounding is done at 12Z (4AM PST).  If a front comes through, the sounding is no longer valid. The sounding becomes less valid later in the day.

Thermal Ceiling: the lower of the height at which the thermal stops rising and the cloud level.  We can't fly into the clouds, so it doesn't matter how much higher the thermal goes.  Remember that we can't get to the top of the thermal because of our sink rate.  Our upper limit will be lower than the reported ceiling.

Soaring Ceiling: We will stop going up when the thermal is rising just fast enough to offset our sink.  It is estimated that this happens when the temperature difference between the thermal and the surrounding air is about 2 degrees F. This number is an estimate of the maximum altitude we might reach if we start at launch height, and should be more reflective of our chances of soaring than the thermal top. Please let me know how this compares with actually flying, and I will adjust it as necessary.

Above Launch: The difference between how high we might get and how high we start. This estimate does not account for ridge lift.

High Temp: This estimate is taken from the National Weather Service website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service estimate of cloudiness, and the angle of the sun.  When the sun is directly overhead on a sunny day, the puddle temp is esimated to be 25 degrees warmer than the high ambient temperature. This estimate now includes a rigorous calculation of the Sun Angle, and accounts for the seasonal differences in zenith and daylight hours.

Wind: This estimate is taken from the National Weather Service website.

Thermal Type: Blue (no cloud formation) or White (Cloud formation)

Thermal Index: This is the maximum difference in temperature between the rising packet of air (the thermal) and the surrounding air.  The difference in temperature is responsible for the buoyancy of the thermal, and larger temperature differences mean faster rising thermals.  A value of about 10 F or greater often means that the conditions are soarable.  Values above 20 could indicate rowdy thermals.

Validity of estimate: Many factors (including strong wind, fronts, cloud shadows, incorrectly predicted temperatures, etc) can affect the validity of the estimates. 

Author: Tad Hurst